The present invention relates to a variable gain amplifier of the type having a logarithmically linearly controlled amplification gain.
Conventional variable gain amplifiers of the logarithmic linear type comprise a multiplier and an exponential converter which converts a gain control signal to a signal having an exponentially variable characteristic. The multiplier provides multiplication of input signal by the output of an exponential converter. The gain of this type of amplifier is a logarithmically linear function of the gain control signal. However, the exponential converter is complex and expensive. The exponential circuit would be further complicated if the gain control were performed by a digital signal since the circuit would be required to process a larger number bits than the number of bits needed to resolve the gain control range.